Shaft drives are usually thought to be less efficient, because of the two 90-degree direction changes required. One at the front, from the transverse engine and transmission to the drive shaft, and one at the back from the longitudinal drive shaft to the rear wheel. Bikes with longitudinal crankshafts and transmissions, such as BMW, Moto Guzzi, Gold Wings, and others have only one directional change so lose less efficiency.

Shaft drive bikes have another quirk called "shaft jacking." When power is applied the rear of the bike tends to rise, or "jack." When power is cut, the rear tends to squat. With chain or belt drive, power application tends to make the rear squat. The problem is more noticeable with higher power. Either system can be so engineered as to eliminate the effects, but the suspension becomes more intricate and costly. It seems a minor point, but consider the case when one is leaned over in a corner and parts start to drag. Reducing the power by closing the throttle is one of the natural reactions. With a chain the rear tends to rise, and the dragging is reduced. With a shaft reducing the power makes the rear drop and actually makes the dragging worse.

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www.scootworks.com manufactures and markets belt drive conversion kits for many chain driven Cruisers and Standards such as the VZ800 Marauder, EN500 & VN800 Vulcans, VLX600 Shadow, VT750 Shadow Ace & Spirit and Triumph Bonneville.

I just hate the looks of big ass rear pulleys. They look like they came from an industrial HVAC system or something. They look bulky -- I like my bikes to look lean. I customize by removing stuff.

And, to me, a chain says I'm a real motorcyclist, not some poser dilettante who doesn't know how to fix his bike, who just got into because it's the current cool thing. Woo-hoo, look at me! I'm like "American Chopper!" Sure, many real motorcyclists like belt drive. Fine, but I don't.

My wifes GN400 had 25000 miles when traded in with original chain but I had it geared 2 teeth on front gear higher.My Suzuki 1500 only shows the drive shaft reaction in low gear,lifts rear of bike  on hard acceleration.

Ah, but if you only knew what your belt or chain was saying about you when you're not around. They're real blabbermouths and liars.